@@ -32,4 +32,18 @@ config EC_ACER_ASPIRE1
laptop where this information is not properly exposed via the
standard ACPI devices.
+config EC_LENOVO_YOGA_C630
+ tristate "Lenovo Yoga C630 Embedded Controller driver"
+ depends on I2C
+ help
+ Driver for the Embedded Controller in the Qualcomm Snapdragon-based
+ Lenovo Yoga C630, which provides battery and power adapter
+ information.
+
+ This driver provides battery and AC status support for the mentioned
+ laptop where this information is not properly exposed via the
+ standard ACPI devices.
+
+ Say M or Y here to include this support.
+
endif # ARM64_PLATFORM_DEVICES
@@ -6,3 +6,4 @@
#
obj-$(CONFIG_EC_ACER_ASPIRE1) += acer-aspire1-ec.o
+obj-$(CONFIG_EC_LENOVO_YOGA_C630) += lenovo-yoga-c630.o
new file mode 100644
@@ -0,0 +1,290 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022-2024, Linaro Ltd
+ * Authors:
+ * Bjorn Andersson
+ * Dmitry Baryshkov
+ */
+#include <linux/auxiliary_bus.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/irqreturn.h>
+#include <linux/lockdep.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/notifier.h>
+#include <linux/slab.h>
+#include <linux/platform_data/lenovo-yoga-c630.h>
+
+#define LENOVO_EC_RESPONSE_REG 0x01
+#define LENOVO_EC_REQUEST_REG 0x02
+
+#define LENOVO_EC_UCSI_WRITE 0x20
+#define LENOVO_EC_UCSI_READ 0x21
+
+#define LENOVO_EC_READ_REG 0xb0
+#define LENOVO_EC_REQUEST_NEXT_EVENT 0x84
+
+#define LENOVO_EC_UCSI_VERSION 0x20
+
+struct yoga_c630_ec {
+ struct i2c_client *client;
+ struct mutex lock;
+ struct blocking_notifier_head notifier_list;
+};
+
+static int yoga_c630_ec_request(struct yoga_c630_ec *ec, u8 *req, size_t req_len,
+ u8 *resp, size_t resp_len)
+{
+ int ret;
+
+ lockdep_assert_held(&ec->lock);
+
+ ret = i2c_smbus_write_i2c_block_data(ec->client, LENOVO_EC_REQUEST_REG,
+ req_len, req);
+ if (ret < 0)
+ return ret;
+
+ return i2c_smbus_read_i2c_block_data(ec->client, LENOVO_EC_RESPONSE_REG,
+ resp_len, resp);
+}
+
+int yoga_c630_ec_read8(struct yoga_c630_ec *ec, u8 addr)
+{
+ u8 req[2] = { LENOVO_EC_READ_REG, };
+ int ret;
+ u8 val;
+
+ guard(mutex)(&ec->lock);
+
+ req[1] = addr;
+ ret = yoga_c630_ec_request(ec, req, sizeof(req), &val, 1);
+ if (ret < 0)
+ return ret;
+
+ return val;
+}
+EXPORT_SYMBOL_GPL(yoga_c630_ec_read8);
+
+int yoga_c630_ec_read16(struct yoga_c630_ec *ec, u8 addr)
+{
+ u8 req[2] = { LENOVO_EC_READ_REG, };
+ int ret;
+ u8 msb;
+ u8 lsb;
+
+ /* don't overflow the address */
+ if (addr == 0xff)
+ return -EINVAL;
+
+ guard(mutex)(&ec->lock);
+
+ req[1] = addr;
+ ret = yoga_c630_ec_request(ec, req, sizeof(req), &lsb, 1);
+ if (ret < 0)
+ return ret;
+
+ req[1] = addr + 1;
+ ret = yoga_c630_ec_request(ec, req, sizeof(req), &msb, 1);
+ if (ret < 0)
+ return ret;
+
+ return msb << 8 | lsb;
+}
+EXPORT_SYMBOL_GPL(yoga_c630_ec_read16);
+
+u16 yoga_c630_ec_ucsi_get_version(struct yoga_c630_ec *ec)
+{
+ u8 req[3] = { 0xb3, 0xf2, };
+ int ret;
+ u8 msb;
+ u8 lsb;
+
+ guard(mutex)(&ec->lock);
+
+ req[2] = LENOVO_EC_UCSI_VERSION;
+ ret = yoga_c630_ec_request(ec, req, sizeof(req), &lsb, 1);
+ if (ret < 0)
+ return ret;
+
+ req[2] = LENOVO_EC_UCSI_VERSION + 1;
+ ret = yoga_c630_ec_request(ec, req, sizeof(req), &msb, 1);
+ if (ret < 0)
+ return ret;
+
+ return msb << 8 | lsb;
+}
+EXPORT_SYMBOL_GPL(yoga_c630_ec_ucsi_get_version);
+
+int yoga_c630_ec_ucsi_write(struct yoga_c630_ec *ec,
+ const u8 req[YOGA_C630_UCSI_WRITE_SIZE])
+{
+ int ret;
+
+ mutex_lock(&ec->lock);
+ ret = i2c_smbus_write_i2c_block_data(ec->client, LENOVO_EC_UCSI_WRITE,
+ YOGA_C630_UCSI_WRITE_SIZE, req);
+ mutex_unlock(&ec->lock);
+
+ return ret < 0 ? ret : 0;
+}
+EXPORT_SYMBOL_GPL(yoga_c630_ec_ucsi_write);
+
+int yoga_c630_ec_ucsi_read(struct yoga_c630_ec *ec,
+ u8 resp[YOGA_C630_UCSI_READ_SIZE])
+{
+ int ret;
+
+ mutex_lock(&ec->lock);
+ ret = i2c_smbus_read_i2c_block_data(ec->client, LENOVO_EC_UCSI_READ,
+ YOGA_C630_UCSI_READ_SIZE, resp);
+ mutex_unlock(&ec->lock);
+
+ return ret < 0 ? ret : 0;
+}
+EXPORT_SYMBOL_GPL(yoga_c630_ec_ucsi_read);
+
+static irqreturn_t yoga_c630_ec_thread_intr(int irq, void *data)
+{
+ u8 req[] = { LENOVO_EC_REQUEST_NEXT_EVENT };
+ struct yoga_c630_ec *ec = data;
+ u8 event;
+ int ret;
+
+ mutex_lock(&ec->lock);
+ ret = yoga_c630_ec_request(ec, req, sizeof(req), &event, 1);
+ mutex_unlock(&ec->lock);
+ if (ret < 0)
+ return IRQ_HANDLED;
+
+ blocking_notifier_call_chain(&ec->notifier_list, event, ec);
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * yoga_c630_ec_register_notify - Register a notifier callback for EC events.
+ * @ec: Yoga C630 EC
+ * @nb: Notifier block pointer to register
+ *
+ * Return: 0 on success or negative error code.
+ */
+int yoga_c630_ec_register_notify(struct yoga_c630_ec *ec, struct notifier_block *nb)
+{
+ return blocking_notifier_chain_register(&ec->notifier_list, nb);
+}
+EXPORT_SYMBOL_GPL(yoga_c630_ec_register_notify);
+
+/**
+ * yoga_c630_ec_unregister_notify - Unregister notifier callback for EC events.
+ * @ec: Yoga C630 EC
+ * @nb: Notifier block pointer to unregister
+ *
+ * Unregister a notifier callback that was previously registered with
+ * yoga_c630_ec_register_notify().
+ */
+void yoga_c630_ec_unregister_notify(struct yoga_c630_ec *ec, struct notifier_block *nb)
+{
+ blocking_notifier_chain_unregister(&ec->notifier_list, nb);
+}
+EXPORT_SYMBOL_GPL(yoga_c630_ec_unregister_notify);
+
+static void yoga_c630_aux_release(struct device *dev)
+{
+ struct auxiliary_device *adev = to_auxiliary_dev(dev);
+
+ kfree(adev);
+}
+
+static void yoga_c630_aux_remove(void *data)
+{
+ struct auxiliary_device *adev = data;
+
+ auxiliary_device_delete(adev);
+ auxiliary_device_uninit(adev);
+}
+
+static int yoga_c630_aux_init(struct device *parent, const char *name,
+ struct yoga_c630_ec *ec)
+{
+ struct auxiliary_device *adev;
+ int ret;
+
+ adev = kzalloc(sizeof(*adev), GFP_KERNEL);
+ if (!adev)
+ return -ENOMEM;
+
+ adev->name = name;
+ adev->id = 0;
+ adev->dev.parent = parent;
+ adev->dev.release = yoga_c630_aux_release;
+ adev->dev.platform_data = ec;
+
+ ret = auxiliary_device_init(adev);
+ if (ret) {
+ kfree(adev);
+ return ret;
+ }
+
+ ret = auxiliary_device_add(adev);
+ if (ret) {
+ auxiliary_device_uninit(adev);
+ return ret;
+ }
+
+ return devm_add_action_or_reset(parent, yoga_c630_aux_remove, adev);
+}
+
+static int yoga_c630_ec_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct yoga_c630_ec *ec;
+ int ret;
+
+ ec = devm_kzalloc(dev, sizeof(*ec), GFP_KERNEL);
+ if (!ec)
+ return -ENOMEM;
+
+ mutex_init(&ec->lock);
+ ec->client = client;
+ BLOCKING_INIT_NOTIFIER_HEAD(&ec->notifier_list);
+
+ ret = devm_request_threaded_irq(dev, client->irq,
+ NULL, yoga_c630_ec_thread_intr,
+ IRQF_ONESHOT, "yoga_c630_ec", ec);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "unable to request irq\n");
+
+ ret = yoga_c630_aux_init(dev, YOGA_C630_DEV_PSY, ec);
+ if (ret)
+ return ret;
+
+ return yoga_c630_aux_init(dev, YOGA_C630_DEV_UCSI, ec);
+}
+
+
+static const struct of_device_id yoga_c630_ec_of_match[] = {
+ { .compatible = "lenovo,yoga-c630-ec" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, yoga_c630_ec_of_match);
+
+static const struct i2c_device_id yoga_c630_ec_i2c_id_table[] = {
+ { "yoga-c630-ec", },
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, yoga_c630_ec_i2c_id_table);
+
+static struct i2c_driver yoga_c630_ec_i2c_driver = {
+ .driver = {
+ .name = "yoga-c630-ec",
+ .of_match_table = yoga_c630_ec_of_match
+ },
+ .probe = yoga_c630_ec_probe,
+ .id_table = yoga_c630_ec_i2c_id_table,
+};
+module_i2c_driver(yoga_c630_ec_i2c_driver);
+
+MODULE_DESCRIPTION("Lenovo Yoga C630 Embedded Controller");
+MODULE_LICENSE("GPL");
new file mode 100644
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022-2024, Linaro Ltd
+ * Authors:
+ * Bjorn Andersson
+ * Dmitry Baryshkov
+ */
+
+#ifndef _LENOVO_YOGA_C630_DATA_H
+#define _LENOVO_YOGA_C630_DATA_H
+
+struct yoga_c630_ec;
+struct notifier_block;
+
+#define YOGA_C630_MOD_NAME "lenovo_yoga_c630"
+
+#define YOGA_C630_DEV_UCSI "ucsi"
+#define YOGA_C630_DEV_PSY "psy"
+
+int yoga_c630_ec_read8(struct yoga_c630_ec *ec, u8 addr);
+int yoga_c630_ec_read16(struct yoga_c630_ec *ec, u8 addr);
+
+int yoga_c630_ec_register_notify(struct yoga_c630_ec *ec, struct notifier_block *nb);
+void yoga_c630_ec_unregister_notify(struct yoga_c630_ec *ec, struct notifier_block *nb);
+
+#define YOGA_C630_UCSI_WRITE_SIZE 8
+#define YOGA_C630_UCSI_CCI_SIZE 4
+#define YOGA_C630_UCSI_DATA_SIZE 16
+#define YOGA_C630_UCSI_READ_SIZE (YOGA_C630_UCSI_CCI_SIZE + YOGA_C630_UCSI_DATA_SIZE)
+
+u16 yoga_c630_ec_ucsi_get_version(struct yoga_c630_ec *ec);
+int yoga_c630_ec_ucsi_write(struct yoga_c630_ec *ec,
+ const u8 req[YOGA_C630_UCSI_WRITE_SIZE]);
+int yoga_c630_ec_ucsi_read(struct yoga_c630_ec *ec,
+ u8 resp[YOGA_C630_UCSI_READ_SIZE]);
+
+#define LENOVO_EC_EVENT_USB 0x20
+#define LENOVO_EC_EVENT_UCSI 0x21
+#define LENOVO_EC_EVENT_HPD 0x22
+#define LENOVO_EC_EVENT_BAT_STATUS 0x24
+#define LENOVO_EC_EVENT_BAT_INFO 0x25
+#define LENOVO_EC_EVENT_BAT_ADPT_STATUS 0x37
+
+#endif